Prince William speaks French in address on ocean protection

The Prince of Wales has warned that the ocean floor is "diminishing before our eyes" and is calling for ambitious action "on a global, national and local level".

Prince William spoke in both English and French as he laid out the risk to the world's oceans at the Blue Economy and Finance Forum in Monaco on Sunday.

"Watching human activity reduce beautiful sea forests to barren deserts at the base of our oceans is heartbreaking," he said at the Grimaldi Forum, named after Monaco's royal family.

"For many, it is an urgent wake up call to just what is going on in our oceans. But it can no longer be a matter of 'out of sight, out of mind'."